Spark plug for internal-combustion motors



, 1949' E. MURPHY ET AL 2,490,646

SPARK PLUG FOR INTERNAL-COMBUSTION MOTORS Filed Jan. 21, 1947 INVENTORS 504 900 flam /1g 1/5- #04: Jan/v CAM/ 414 Patented Dec. 6, 1949 2,490,646 SPARK PLUG For: INTERNAL-COMBUSTION MOTORS Eduardo Murphy, J os Mul, and Juan Caniglia, Rosario, Argentina Application January 21, 1947, Serial No. 723,280 In Argentina December 16, 1946 "2 Claims.

"This invention relates to improvements in .Per lu s. r, n na qenbu n o rs and more particularlyto improvements related to the cleaning of these spark plugs,

rr tice'has shown that the opposite end's of i'l'e 'fie' k lfii rci e e i' e w v y e fticles "oi lubricant-or byother -factors, with the consequent unsatisfactory operation of the spark Sn s esu im' f n 'ie s i i i n, i reh- Jlm. S ee S lve i Part by mp in he Q al t s 1 he iendl ri e t end e by RlQVifi hei'natjerian used in the construction 16 l f rs hi ir dus h jt minim m t extraneous particles which might stain the sensitivepart'sofithe sparlg'plugs. V

However, if the failurement'ioned hereinbefor'e does happen, itjis neces'sary to disconnect the foable'onnected to the central electrode of spark plug, unscrewfthe spark plug, clean the same, l,

place it again in its'plac'e and to connect anew itscentral electrode to the ignition circuit The simple enumeration of the various'operations reuired is a clearjndication "of the time required i9? ir t heffei t, qn d. be en o ed that sometimes'it is necessary to clean ally-or at least several, of the spark plugs since notalways {it ispossible to locate "exactly the faulty one. Furthermore, the cleaning of 'spark plugs on the iroadisoften veryinconvenientsuch as'on rainy d ys.

H 'Ajfurther field'ofapplioation of thejp'resent inyention are the motors used in boats "in which a rapidcleaning of the spark plugs offers multiple iadventages mee in th'e presence of a strong cur- Qi'erit 'andfwith ther'notor'dead, the boat is driftinfg wh'lch somtim'e's might have very serious consequenc s, H V r w v The mlir v mh c rdin to the s n nyentio have for'their object to eliminate 'all of the'abovedisadvantages and, above all, to provide an elfective solution for the problem.

Bri'e'fl'y stated,;the improvements introduced in theses-r1; plugs for internal combustion motors, whiohcon'stitute the presentfinvention, 'consist of ificesformed intheibody of 'the'spa p u and unicatirig with 'thej'eiiterior, the chamber fisformd in the interior'of said body betw'e'e the"iritrnaljsurfacethereof and the central ensionloi jtheic'entral electrode support, said fifces bein'g'located in'pointswhich'arenot covered when "the spark "plug is mounted in the 'c rrespondin gcylinder'iof a motor andbeing pro- IYl fi w th me n [f r vev e ne, t pass q ,flidsjand other materials which might pass theretlii'olfgh.

ttain the above. it will be evident thatfone'df the'main objects andadvantages of the invention consists in providingthe facilityof rapidly cleanifi'g the spark plligs without it being nces'saryto unserewthem fromthe motor.

V Afurth'erobject of the present invention is to provide, by meafis of the improvements introduced into tn 'sparl: plugs 'and their accessories, an efiicient device-of "simple construction, easy handling 'and reduced cost. V

7 Astill further object'is to'provide aspark plug which practicallydoes not produce'cleaning costs.

furthr'objet of'this invention is to provide a sp'ark plu'g which'may be operated with an ample margin o safety, notwithstanding the velocity and pressure required during the operation, due to t esimpncipy of theineoha'nisrn resulting from the'abov combination.

Flilthl' objects and advantage's'of thisinven tioh will become apparent in the course of the renewing description taken 'in conjunction with the accompanying drawings, wherein:

Fig, 1 'is'fa side elevation, partly inseotion, of a spark plug-including the improvements according to the present invention "and'de'signed for an internal combustion motors of the type used in vehicles, 7 I

Fig. 2 'is' fa side elevation, partly in section, ora further embodiment of the invention. I V

"Fig. 3 is a view, partly in section, of a further embodiment of the present invention, and finally Fig. 4 is a 'side elevation, partly in section, of fa spark plug mounted on thecylinoler head of an internal combustion motor.

intheva'rious figurs'the'same or similarparts tenements have been designated with the same reference numerals or characters.

Ascanbe observedin the drawings, aisa spark plug formed of the insulating body for the central electrode 1 which forms the inner shoulder 2 of the spark plug body 3 (Fig.1). The upper e xternalpart of said spark plug body '3 is 'pro- "vided with a hexagonal nut/l by means of which the internal threaded portion 5 of body -3 is screwed into the corresponding cylinder of the -inotor. Between the cylindrical portion '6 and threaded portionli there exists'a cylindrical part, :the "diameter of "which is smaller than the in- ?ternal diameter "of thread '5, thus forming neck Twit hr'espe'ct to thread 5 and Tim 8 which is located immediately below cylindrical "portion '6.

reduced 'portion or neck -l preferably is iorovided witih three radial passages or orifices 9 located a nea-r aspos'sible with respect to rirnor configuration of which is cylindrical, forms the lower portion of said bushing Hi. In view of the fact that the height of bushing ID is equal to the sum of the elements mentioned hereinbefore, there is formed, in that portion corresponding to neck I, an annular chamber H between said neck portion 1 and the internal face of bushing Iii.

Bushing i is provided with a radial aperture I! closed by a cock or valve l3.

The operating principle on which the cleaning of the spark plug is based, is rather simple. Should the central electrode or the other electrode 15 of the spark plug be stained or dirty, it is sufficient to open valve i3, either mechanically or manually, to obtain a communication between the interior of the cylinder and the exterior of the motor. 0n running the motor, either connected to a load or the pressure originated within the cylinder by the piston during the compression stroke is considerably higher than the atmospheric pressure, and since there exists a communication between the interior of the cylinder and the exterior of the motor, the internal pressure is relieved through said passage the stream of compressed gases or air sweeping along all particles which it encounters on its passage from the interior of cylinder toward the exterior of the motor. In other words, the trajectory described by the compressed gases has been indicated by the arrows illustrated in Fig. 1, i. e. the compressed gas or gases flows through the chamber l6 formed by the internal wall I! of the spark plug body 3 and the central extension ll! of insulating body I, enters annular chamber ll through orifices 9 and passes, through valve 13, to the exterior of the motor.

It should be noted that instead of a valve or cook, illustrated in Fig. 1, it is possible, should it be considered convenient, to increase the number of apertures 12 and consequently the number of valves l3 or of other adequate passage governing means.

A particular feature of the present'invention is that orifices 9 should be located as near as possible to shoulder 8, so that the compressed gas or gases must follow a larger trajectory and hence offer a larger security in sweeping along all extraneous particles.

As regards Fig. 2, the same represents a further embodiment of the present invention.

In order to obtain a correct operation of the spark plug cleaning system, it is necessary that an annular space exists between the bushing and the spark plug. In the case of bushing [9, the latter is provided with an internal recess which, in combination with recess 20, forms annular chamber 2i. Since annular chamber 2| is formed by bushing 19, it is not necessary to reduce the diameter of the cylindrical body. 22. Valve 23, which controls the discharge of the dirt, might be, as illustrated in the present case, of the direct manual type and is governed by means of handle 24. The arrangement of the other parts or elements is exactly equal to that described in connection with Fig. 1 and for this reason, Fig. 2 shows only in detail those parts which have been modified according to this embodiment of the invention.

For the sake of information, and without unduly limiting thereby the scope of the present invention, it can be mentioned that there exists a possibility of eliminating completely the bushing as well as the neck portion, by providing each orifice 9 with a corresponding individual valve or cook- 25. The most practical embodiment of this idea consists in perforating two orifices 9 in the body 3 of the spark plug, and mounting in each of said orifices an individual valve 25 having a horizontal shaft 26. Said valves 25 might be governed by remote control, for instance from the instrument board-of the car or r y other remote point. One of the fifil q 0f the remote control system consists JP fltllizmg Worm wheel 21 mounted on the shaftic 9 f 25 f a worm (not shown in Fig. 3) whljl fi Wm 13 governed, for instance, by a flexible" shaft-f said worm to a knob mounted in the dashx of the vehicle.

Finally, Fig. 4 shows part of a motor 6 pro" vided with a depression 33 in which there is mounted a spark plug a incorporating the improvements according to the present invention.- As can be clearly seen in the above mentioned" figure, the lower cylindrical portion of bushing l0 must have a height equal to at least that of depression 33 of motor b, in order that part [0 of bushing l0 remains above motor b so that valve 13 mounted in said bushing I0, is located above motor b. In the present case, the figure shows a valve having a vertical shaft 28 on which there is mounted a worm wheel 29 meshing with a worm 29 mounted on brackets 34 welded or otherwise fixed to valve 13. In order to rotate said worm 29' the same has been coupled to a flexible shaft 30, the other extreme of which terminates in a knob 3| mounted on the dash board of the respective vehicle.

The invention is not to be construed aslimitect to the particular embodiments that have been disclosed, since these are illustrative, but the scope of the invention is indicated in the claims.

We claim:

1. In an internal combustion engine havinga plurality of cylinders, a reciprocating piston for each cylinder, and a spark plug for each cylinder, the improvement in each of the spark plugs which comprises a hollow body provided at one end portion with an inwardly projecting electrode, an inner part providing at its lower end an elec trode cooperating with said first electrode, a groove on the exterior of said hollow body, a bushing surrounding said body and forming with said groove a chamber, passages within said body between the chamber and the interior of said body; in combination with independent means for cleaning each of said plugs independently of each other which means includes a pipe secured to said bushing and communicating with said chamber and the atmosphere, a stop valve in said pipe, an individually upwardly extending shaft for operating said valve, gearing on the upper portion of said shaft meshing with gearing on a second shaft and manually remote con,- trolled means for rotating said second shaft.

2. In an internal combustion engine having a. plurality of cylinders, a reciprocating piston for each cylinder and a spark plug for each cylinder, the improvement in each of the spark plugs which comprises a hollow body provided at one end portion with an inwardly projecting electrode, an inner part providing at its lower end an electrode cooperating with said first electrode, a groove on the exterior of said hollow body, a bushing surrounding said body and forming with said groove a chamber, passages in said body between said chamber and the interior of said body; in combination with independent means for cleaning each of said plugs independently of each other which means includes a pipe secured to said bushing and communicating with said chamber and the atmosphere, a stop valve in said pipe, an individually upwardly extending shaft for operating said valve, gearing on the upper portion of said shaft meshing with gearing on a second shaft and manually remote controlled means for rotating said second shaft, bearings for supporting said second shaft carried by upwardly ex- REFERENCES CITED The following references are of record in the file of this patent:

. UNITED STATES PATENTS Number Name Date 1,395,923 McCoy Nov. 1, 1921 1,492,007 Wayte Apr. 29, 1924 1,543,646 Shamblin June 23, 1925 

